I purchased some large art bundles from the Unity asset store. Backgrounds, icons, and special effects always have been my weaknesses, so just buying royalty free art is a sensible investment. Having the art early on can influence design in unexpected and beneficial ways too.
I will continue to paint and animate my own characters. I use a tool called Spine which allows me to programmatically interchange pieces like weapons and gear. I chose to use animals as the fantasy heroes because it fits better in the premise of the game. Plus, animals are gender-neutral, and it rids having to be politically correct in having a specific number of different races, especially for a game that will be localized worldwide.